This is a semi-phonetic corruption of the the word "bourgeois." The blues singer (and communist) Leadbelly wrote a song called the "Bourgeois Blues." The refrain was: It's a bushwa town, It's a bushwa town."

Bushwa is used to indicate that something is reactionary or allied with the property class. Leadbelly wrote the song in 1946 in disgust at being denied service at Washington D.C. restaurants.